Patent GB-409704-A (GB)
Title: Improvements relating to bore hole pump equipments
IPC: F04D13/08
Filed: 1932-11-01
Abstract: 409,704. Centrifugal pumps. POTTER, A. C., Dysart Road Iron Works, Grantham, Lincolnshire. Nov. 1, 1932, Nos. 30805/32 and 20745/33. [Class 110 (i).] A bore-hole pump equipment, in which the motor 2 is housed in an air chamber 3, is removably supported by a tube 4 serving as the rising main ; the supply of current to the motor is effected by leads and contacts associated with the tube, and contacts on the casing of the machines. The lower end of the tube 4 carries a ring 5 upon which the pump 1 and motor 2 are supported by resilient rings 76, 77. Contacts on the ring 5 are connected to leads in the groove 74 in the ring, and these are connected through the terminal box 73 to leads 71 secured by clips 72 to the tube 4. The lower ends of these leads are looped and protected by a guard 86. The contacts on the ring 5 engage with spring contacts 78 connected to the motor and disposed in recesses in ring 77 on the pump set. The pump may have two impellers, oppositely disposed so that their axial thrusts are balanced. The lower end of the tube 4 has an extension 48, Fig. 3, closed by a plate 49 and a valve 51 normally held upwards in its closed position by a spring 53. The suction inlet 1 of the pump is enclosed by a tube supporting a cylinder 1<a> containing a piston 1<b> with an extension rod 1<e> to engage the head of the spindle of the valve 51. The piston has passages 1<c> normally closed by a non-return valve 1<a> and is provided with springs 1 to engage in recesses in the cylinder wall. When the pump set is lowered, the valve 51 is closed so that the closure of the contacts is effected in the absence of liquid. Air under pressure is then forced into the tube 4 and the piston 1<b> is forced downwards until the springs 1<i> move into the recesses to hold the piston in the position in which it depresses the valve 51. The parts are then in their operating positions and the packing rings 76, 77 prevent liquid from reaching the electric contacts. To recharge the air chamber of the motor, air is again introduced into the tube 4 and forces the piston down until the ports 1<j> in the cylinder wall are uncovered; liquid passes out through these ports and compressed air rises through the pump passages to the air chamber. The casing of the pump set has ribs 80, inclined to the axis as shown in Fig. 4, which engage with elements 81 on the interior of the tube 4 so that the contacts 78 are brought into the correct position to meet the contacts on the ring 5. In a modification, the tube 4 is extended below the seating ring. 5 and the air passages through the pump set are lengthened to a corresponding extent. Where the liquid is charged with grit or sediment an auxiliary seating ring 89, Fig. 10, is disposed above the main seating ring 5, and the pump discharge passes from the chamber thus formed into discharge pipes 92 attached to the tube 4 which in this case does not carry liquid. In some cases, for example, in mines, pump sets of this type may be used in series ; the tube 4 with the pump set 1, 2 is supported in slides from the platform 93, so that its position with regard to the platform can be adjusted, while the second pump set is supported on the platform. The tubes in which the pump sets are supported are provided with inspection doors 105. In a further modification, as shown in Fig. 14, the pump set is supported directly from the rising main 34; the pump discharge passes into an annular chamber 1<a> and thence to the main 34 through tubes 1<b>. Specification 404,993 is referred to.